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Abstract: Dried parsley is regularly contaminated with foodborne pathogens, especially Salmonella. Application of contaminated ingredients in ready-to-eat dishes without further thermal treatment represents a considerable health risk. This study examined the suitability of pulsed light as a novel decontamination method of Salmonella in dried parsley, along with the impact on selected quality parameters (chlorophyll content, phenolic compounds, color, and odor) and product characters (temperature and water activity value). Samples were inoculated with one of three Salmonella isolates (Salmonella Cerro or one of two isolates of Salmonella Agona) at two contamination levels of 103 or 107 CFU/g and treated under various experimental factors, including distance to the light source and exposure time, resulting in fluences in the range of 1.8 to 19.9 J/cm2. At selected parameter settings (9.8 and 13.3 J/cm2), the effect of prolonged storage time (48 h) of inoculated samples before treatment on the reduction of Salmonella Cerro was examined. Samples treated at the same fluences were also stored for 35 days at 22 to 25°C. The three Salmonella isolates were significantly reduced by pulsed light (P < 0.05). Reduction factors ranged between 0.3 and 5.2 log CFU with varying sensitivities of the isolates. In general, increasing fluences (depending on exposure time and distance to the light source) resulted in increasing reductions of Salmonella. However, on closer examination, exposure time and distance to the light source had a varying influence on the reduction of the different Salmonella isolates. Decreasing reduction factors were observed by increasing the contamination level and prolonging the storage time of inoculated samples before treatment. No undesirable changes in quality parameters and sensory analysis were detectable at fluences of 9.8 and 13.3 J/cm2, indicating that pulsed light may be a suitable alternative for the decontamination of dried parsley., (Copyright ©, International Association for Food Protection.)

MYC is an oncogenic transcription factor that binds globally to active promoters and promotes transcriptional elongation by RNA polymerase II (RNAPII) 1,2 . Deregulated expression of the paralogous protein MYCN drives the development of neuronal and neuroendocrine tumours and is often associated with a particularly poor prognosis 3 . Here we show that, similar to MYC, activation of MYCN in human neuroblastoma cells induces escape of RNAPII from promoters. If the release of RNAPII from transcriptional pause sites (pause release) fails, MYCN recruits BRCA1 to promoter-proximal regions. Recruitment of BRCA1 prevents MYCN-dependent accumulation of stalled RNAPII and enhances transcriptional activation by MYCN. Mechanistically, BRCA1 stabilizes mRNA decapping complexes and enables MYCN to suppress R-loop formation in promoter-proximal regions. Recruitment of BRCA1 requires the ubiquitin-specific protease USP11, which binds specifically to MYCN when MYCN is dephosphorylated at Thr58. USP11, BRCA1 and MYCN stabilize each other on chromatin, preventing proteasomal turnover of MYCN. Because BRCA1 is highly expressed in neuronal progenitor cells during early development 4 and MYC is less efficient than MYCN in recruiting BRCA1, our findings indicate that a cell-lineage-specific stress response enables MYCN-driven tumours to cope with deregulated RNAPII function.

p53 induces cell death upon DNA damage, but this may not confer all of its tumor suppressor activity. We report that p53 activation enhances the processivity of DNA replication, as monitored by multi-label fiber assays, whereas removal of p53 reduces fork progression. This is observed in tumor-derived U2OS cells but also in murine embryonic fibroblasts with heterozygous or homozygous p53 deletion and in freshly isolated thymocytes from mice with differential p53 status. Mdm2, a p53-inducible gene product, similarly supports DNA replication even in p53-deficient cells, suggesting that sustained Mdm2-expression is at least one of the mechanisms allowing p53 to prevent replicative stress. Thus, p53 helps to protect the genome during S phase, by preventing the occurrence of stalled or collapsed replication forks. These results expand p53's tumor-suppressive functions, adding to the ex-post model (elimination of damaged cells) an ex-ante activity; i.e., the prevention of DNA damage during replication., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: A variety of microbial communities exist throughout the human and animal body. Genetics, environmental factors and long-term dietary habit contribute to shaping the composition of the gut microbiota. For this reason the study of the gut microbiota of a mammal exhibiting an extraordinary life span is of great importance. The naked mole-rat (Heterocephalus glaber) is a eusocial mammal known for its longevity and cancer resistance., Methods: Here we analyzed its gut microbiota by cultivating the bacteria under aerobic and anaerobic conditions and identifying their species by mass spectrometry., Results: Altogether, 29 species of microbes were identified, predominantly belonging to Firmicutes, and Bacteroidetes. The most frequent species were Bacillus megaterium (45.2 %), followed by Bacteroides thetaiotaomicron (19.4 %), Bacteroides ovatus, Staphylococcus sciuri and Paenibacillus spp., each with a frequency of 16.1 %., Conclusion: Overall, the gut of the naked mole-rat is colonized by diverse, but low numbers of cultivable microbes compared with humans and mice. The primary food plants of the rodents are rich in polyphenols and related compounds, possessing anti-microbial, anti-inflammatory, anti-oxidative as well as anti-cancer activity which may contribute to their exceptionally healthy life.